This isn't a video game, and that makes it somewhat unusual for here. But I am using some stuff from OGA, so it's not irrelevant. :)

Keeper of the Cards is a game idea I've been toying with for a couple months. It's a pretty simple concept: it's a trading card game, but anyone can make new cards. The game achieves this by defining a standard set of allowable texts and a standard way of calculating the cost of playing the card.

Gameplay-wise, Keeper of the Cards incorporates ideas from Yu-Gi-Oh (the game I grew up with), Duel Masters (another game I liked as a child), and Arcmage, which from what I gather itself takes a lot of inspiration from Magic: The Gathering. I also added in a dice-rolling mechanic, which randomizes the exact amount of damage an attack inflicts, and a team-fighting mechanic, which allows you to use multiple creatures in a single fight.

So, where does OGA come in? Quite simply, I decided that it's prudent to design some cards for people to use if they don't want to design their own or at the very least don't want to design every single one, and I'm using concept art from here for that. So far, I've put together four card designs, though I've also found 5 more works on OGA that I'm going to make into cards. There really is some very nice stuff here.

Link to the project's Git repo is here for anyone interested:

https://github.com/onpon4/kotc